Electrolyte including electrolyte solvent, fluoroether, and bis(fluorosulfonyl) salt, and lithium metal electrochemical cells including the same

Abstract

Systems, devices, and methods described herein relate to electrolyte formulations and the incorporation thereof into batteries. In some aspects, an electrolyte composition can comprise between about 10 wt % and about 42 wt % of an electrolyte solvent, between about 13 wt % and about 59 wt % of a fluoroether. In some embodiments, the electrolyte solvent can make up between about 26 wt % and about 39 wt % of the composition. In some embodiments, the fluoroether can make up between about 18 wt % and about 36 wt % of the composition. In some embodiments, the composition can include between about 0.5 wt % and about 1.5 wt % of a first additive. In some embodiments, the composition can include between about 0.5 wt % and about 5 wt % of a second additive.

The invention claimed is: 
     
       1. A method of forming an electrolyte, comprising:
 forming a first electrolyte solution, the first electrolyte solution including about 26 wt % to about 70 wt % of a first salt including bis(fluorosulfonyl)imide ions and about 30 wt % to about 74 wt % of a first electrolyte solvent; 
 forming a second electrolyte solution, the second electrolyte solution including about 2 wt % to about 42 wt % of a second salt and about 38 wt % to about 98 wt % of a second electrolyte solvent different from the first electrolyte solvent; 
 combining the first electrolyte solution and the second electrolyte solution to form an electrolyte mixture such that the electrolyte mixture includes about 10 wt % to about 90 wt % of the first electrolyte solution and about 10 wt % to about 90 wt % of the second electrolyte solution; and 
 incorporating the electrolyte mixture into an electrochemical cell such that the electrolyte mixture forms the electrolyte of the electrochemical cell. 
 
     
     
       2. The method of  claim 1 , wherein the electrolyte mixture includes about 20 wt % to about 30 wt % of the first electrolyte solution and about 70 wt % to about 80 wt % of the second electrolyte solution. 
     
     
       3. The method of  claim 1 , wherein the first electrolyte solution comprises an electrolyte additive, the electrolyte additive including at least one of tris-(trimethylsilyl) phosphate (TMSP), trimethoxy (3,3,3-trifluoropropyl)silane (TTS), pentafluorophenyltriethoxysilane (TPS), boric acid tris(trimethylsilyl) ester (TMSB), tris-(pentafluorophenyl)silane (TPFPS), 1,10-sulfonyldiimidazole (SDM), trioxane, lithium difluorophosphate, lithium difluoro oxalato borate, lithium nitrate, (pentafluorophenyl)diphenylphosphine (PFPDPP), cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS), polyethylene-glycol (PEG-8000), benzotriazole (BTA), thiourea (CH 4 N 2 S), sodium dodecyl benzene sulfonate (SDBS), LiTFSI, PVA, PEG, or CMC. 
     
     
       4. The method of  claim 1 , wherein the electrolyte mixture comprises:
 about 10 wt % to about 42 wt % of a product solvent, the product solvent including a mixture of the first electrolyte solvent and the second electrolyte solvent; 
 about 13 wt % to about 43 wt % of a fluoroether (FE); and 
 about 22 wt % to about 43 wt % of the first salt, wherein the FE includes a compound having the following structure: 
 
       
         
           
           
               
               
           
         
         where n1 and n2 each have values between 1 and 5, X=F, Br, Cl, or I, and n=1. 
       
     
     
       5. The method of  claim 1 , wherein the second salt includes LiBF4 in a range of about 4 wt % to 19 wt % of the second electrolyte solution. 
     
     
       6. The method of  claim 1 , wherein bis(fluorosulfonyl) imide ions included in the first salt, or the second salt includes at least one of LiFSI or NaFSI. 
     
     
       7. The method of  claim 6 , wherein the LiFSI or NaFSI is in a range of about 2 wt % to about 42 wt % of the first electrolyte solution. 
     
     
       8. The method of  claim 1 , wherein:
 the first electrolyte solvent includes at least one of 1,2-dimethoxyethane, bis-(2-fluoro-ethyl)-ether, 1,2-diethoxyethane, bis(2-methoxyethyl) ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, diethyl ether, dipropyl ether, 1,2-dipropoxyethane, dibutoxyethane, 1,2-diethoxypropane, dimethyl carbonate, 1,3-dioxolane, 1,4-dioxolane, ethyl methyl carbonate, diethyl carbonate, dimethyl sulfoxide, ethyl vinyl sulfone, tetramethylene sulfone, ethyl methyl sulfone, ethylene carbonate, vinylene carbonate, fluoroethylene carbonate, 4-vinyl-1,3-dioxolan-2-one, dimethyl sulfone, methyl butyrate, ethyl propionate, trimethyl phosphate, triethyl phosphate, gamma-butyrolactone, 4-methylene-1,3-dioxolan-2-one, methylene ethylene carbonate, 4,5-dimethylene-1,3-dioxolan-2-one, allyl ether, triallyl amine, triallyl cyanurate, triallyl isocyanurate, water, carbonate, fluorobutane, or tetrahydropyran; and 
 the second electrolyte solvent includes a fluoroether (FE). 
 
     
     
       9. The method of  claim 8 , wherein the fluoroether includes a compound having the following structure: 
       
         
           
           
               
               
           
         
         where n 1  and n 2  each have values between 1 and 5, X=F, Br, Cl, or I, and n=1. 
       
     
     
       10. The method of  claim 8 , wherein at least one of the first salt or the second salt includes at least one of lithium bis(fluorosulfonyl) imide (F 2 LiNO 4 S 2 ), lithium bis(trifluoromethylsulfonyl) imide (LiC 2 F 6 NO 4 S 2 ), lithium bis(oxalato)borate, lithium hexafluorophosphate (LiPF 6 ), lithium hexafluoroarsenate (LiAsF 6 ), lithium bis(trifluoromethane) sulfonimide (LiN(SO 2 CF 3 ) 2 ), lithium trifluoromethanesulfonate (LiCF 3 SO 3 ), lithium perchlorate (LiClO 4 ), lithium difluoro oxalato borate (LiBF 2 (C 2 O 4 )), lithium iodide (LiI), lithium bromide (LiBr), lithium chloride (LiCl), lithium hydroxide (LiOH), lithium nitrate (LiNO 3 ), lithium 2-trifluoromethyl-4,5-dicyanoimidazole (LiTDI), lithium sulfate (LiSO 4 ), lithium difluorophosphate (LiPO 2 F 2 ), or lithium tetrafluoroborate (LiBF 4 ). 
     
     
       11. The method of  claim 1 , further comprising:
 forming a third electrolyte solution, the third electrolyte solution including a third salt and a third electrolyte solvent; and 
 combining the third electrolyte solution with the first electrolyte solution and the second electrolyte solution to form the electrolyte mixture. 
 
     
     
       12. The method of  claim 11 , wherein the third salt includes at least one of lithium bis(fluorosulfonyl) imide (F 2 LiNO 4 S 2 ), lithium bis(trifluoromethylsulfonyl) imide (LiC 2 F 6 NO 4 S 2 ), lithium bis(oxalato)borate, lithium hexafluorophosphate (LiPF 6 ), lithium hexafluoroarsenate (LiAsF 6 ), lithium bis(trifluoromethane) sulfonimide (LiN(SO 2 CF 3 ) 2), lithium trifluoromethanesulfonate (LiCF 3 SO 3 ), lithium perchlorate (LiClO 4 ), lithium difluoro oxalato borate (LiBF 2 (C 2 O 4 )), lithium iodide (LiI), lithium bromide (LiBr), lithium chloride (LiCl), lithium hydroxide (LiOH), lithium nitrate (LiNO 3 ), lithium 2-trifluoromethyl-4,5-dicyanoimidazole (LiTDI), lithium sulfate (LiSO 4 ), lithium difluorophosphate (LiPO 2 F 2 ), lithium tetrafluoroborate (LiBF 4 ). 
     
     
       13. The method of  claim 11 , wherein the third electrolyte solution includes at least one of 1,2-dimethoxyethane, bis(2-methoxyethyl) ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, diethyl ether, dipropyl ether, 1,2-dipropoxyethane, dibutoxyethane, 1,2-diethoxypropane, bis-(2-fluoro-ethyl)-ether, 1,2-diethoxyethane, dimethyl carbonate, 1,3-dioxolane, 1,4-dioxolane, ethyl methyl carbonate, diethyl carbonate, tetrahydropyran, dimethyl sulfoxide, ethyl vinyl sulfone, tetramethylene sulfone, ethyl methyl sulfone, ethylene carbonate, vinylene carbonate, fluoroethylene carbonate, 4-vinyl-1,3-dioxolan-2-one, dimethyl sulfone, methyl butyrate, ethyl propionate, trimethyl phosphate, triethyl phosphate, gamma-butyrolactone, 4-methylene-1,3-dioxolan-2-one, methylene ethylene carbonate, 4,5-dimethylene-1,3-dioxolan-2-one, allyl ether, triallyl amine, triallyl cyanurate, triallyl isocyanurate, water, carbonate, fluorobutane, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, bis(2,2,2-trifluoroethyl) ether, 1,1,2,2,-tetrafluoroethyl-2,2,2-trifluoroethyl ether, tris(2,2,2-trifluoroethyl)orthoformate, pentafluoroethyl 2,2,2-trifluoroethyl ether, 2,2,3,3,4,4,5,5-octafluoro-1-pentanol, methoxynonafluorobutane, ethoxynonafluorobutane, 2,2,2-trifluoroethyl nonafluorobutanesulfonate, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, bis(2,2,2-trifluoroethyl) ether, 1,1,2,2,-tetrafluoroethyl-2,2,2-trifluoroethyl ether, tris(2,2,2-trifluoroethyl)orthoformate, pentafluoroethyl 2,2,2-trifluoroethyl ether, 2,2,3,3,4,4,5,5-octafluoro-1-pentanol, or 3,3,4,4,5,5-hexafluorotetrahydropyran. 
     
     
       14. A method of forming an electrolyte, comprising:
 forming a first electrolyte solution, the first electrolyte solution including about 26 wt % to about 70 wt % of a first salt and about 30 wt % to about 74 wt % of a first electrolyte solvent; 
 forming a second electrolyte solution, the second electrolyte solution including about 2 wt % to about 42 wt % of a second salt and about 38 wt % to about 98 wt % of a second electrolyte solvent different from the first electrolyte solvent, the second electrolyte solvent including a fluoroether; and 
 combining the first electrolyte solution and the second electrolyte solution to form an electrolyte mixture such that the electrolyte mixture includes about 10 wt % to about 90 wt % of the first electrolyte solution and about 10 wt % to about 90 wt % of the second electrolyte solution, the electrolyte mixture configured to be incorporated into an electrochemical cell to form the electrolyte of the electrochemical cell. 
 
     
     
       15. The method of  claim 14 , wherein the fluoroether includes bis(2-fluoroethyl) ether (BFE). 
     
     
       16. The method of  claim 14 , wherein the first salt includes bis(fluorosulfonyl)imide ions. 
     
     
       17. The method of  claim 14 , wherein the first salt includes at least one of lithium bis(fluorosulfonyl)imide (F 2 LiNO 4 S 2 ), lithium bis(trifluoromethylsulfonyl) imide (LiC 2 F 6 NO 4 S 2 ), lithium bis(oxalato)borate, lithium hexafluorophosphate (LiPF 6 ), lithium hexafluoroarsenate (LiAsF 6 ), lithium bis(trifluoromethane) sulfonimide (LiN(SO 2 CF 3 ) 2 ), lithium trifluoromethanesulfonate (LiCF 3 SO 3 ), lithium perchlorate (LiClO 4 ), lithium difluoro oxalato borate (LiBF 2 (C 2 O 4 )), lithium iodide (LiI), lithium bromide (LiBr), lithium chloride (LiCl), lithium hydroxide (LiOH), lithium nitrate (LiNO 3 ), lithium 2-trifluoromethyl-4,5-dicyanoimidazole (LiTDI), lithium tetrafluoroborate (LiBF 4 ), lithium sulfate (LiSO 4 ), or lithium difluorophosphate (LiPO 2 F 2 ). 
     
     
       18. The method of  claim 14 , wherein the electrolyte mixture includes about 20 wt % to about 30 wt % of the first electrolyte solution and about 70 wt % to about 80 wt % of the second electrolyte solution. 
     
     
       19. The method of  claim 14 , wherein the electrolyte mixture includes about 70 wt % to about 80 wt % of the first electrolyte solution and about 20 wt % to about 30 wt % of the second electrolyte solution. 
     
     
       20. The method of  claim 14 , wherein the electrolyte mixture includes about 40 wt % to about 60 wt % of the first electrolyte solution and about 40 wt % to about 60 wt % of the second electrolyte solution. 
     
     
       21. The method of  claim 14 , wherein the fluoroether includes a compound having the following structure: 
       
         
           
           
               
               
           
         
         where n 1  and n 2  each have values between 1 and 5, X=F, Br, Cl, or I, and n=1. 
       
     
     
       22. The method of  claim 14 , wherein the electrolyte mixture comprises:
 about 10 wt % to about 42 wt % of a product solvent, the product solvent including a mixture of the first electrolyte solvent and the second electrolyte solvent; 
 about 13 wt % to about 43 wt % of the fluoroether (FE); and 
 about 22 wt % to about 43 wt % of the first salt, wherein the FE includes a compound having the following structure: 
 
       
         
           
           
               
               
           
         
         where n1 and n2 each have values between 1 and 5, X=F, Br, Cl, or I, and n=1. 
       
     
     
       23. A method of forming an electrolyte, comprising:
 forming a first electrolyte solution, the first electrolyte solution including a first salt including bis(fluorosulfonyl)imide ions and about 30 wt % to about 74 wt % of a first electrolyte solvent; 
 forming a second electrolyte solution, the second electrolyte solution including a second salt and about 38 wt % to about 98 wt % of a second electrolyte solvent different from the first electrolyte solvent, the second electrolyte solvent including a fluoroether; 
 combining the first electrolyte solution and the second electrolyte solution to form an electrolyte mixture such that the electrolyte mixture includes about 10 wt % to about 90 wt % of the first electrolyte solution and about 10 wt % to about 90 wt % of the second electrolyte solution, the electrolyte mixture configured to be combined with an anode, a cathode, and a separator to form an electrochemical cell, 
 wherein the electrolyte mixture comprises:
 about 10 wt % to about 42 wt % of a product solvent, the product solvent including a mixture of the first electrolyte solvent and the second electrolyte solvent; 
 about 13 wt % to about 59 wt % of the fluoroether (FE); and 
 about 22 wt % to about 43 wt % of the first salt. 
 
 
     
     
       24. The method of  claim 23 , wherein the fluoroether includes a compound having the following structure: 
       
         
           
           
               
               
           
         
         where n 1  and n 2  each have values between 1 and 5, X=F, Br, Cl, or I, and n=1. 
       
     
     
       25. The method of  claim 23 , wherein the electrolyte mixture includes about 20 wt % to about 30 wt % of the first electrolyte solution and between about 70 wt % and about 80 wt % of the second electrolyte solution. 
     
     
       26. The method of  claim 23 , wherein the electrolyte mixture includes about 70 wt % to about 80 wt % of the first electrolyte solution and about 20 wt % to about 30 wt % of the second electrolyte solution. 
     
     
       27. The method of  claim 23 , wherein the electrolyte mixture includes about 40 wt % to about 60 wt % of the first electrolyte solution and about 40 wt % to about 60 wt % of the second electrolyte solution. 
     
     
       28. The method of  claim 23 , wherein the first electrolyte solvent includes at least one of 1,2-dimethoxyethane, bis-(2-fluoro-ethyl)-ether, 1,2-diethoxyethane, bis(2-methoxyethyl) ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, diethyl ether, dipropyl ether, 1,2-dipropoxyethane, dibutoxyethane, 1,2-diethoxypropane, dimethyl carbonate, 1,3-dioxolane, 1,4-dioxolane, ethyl methyl carbonate, diethyl carbonate, dimethyl sulfoxide, ethyl vinyl sulfone, tetramethylene sulfone, ethyl methyl sulfone, ethylene carbonate, vinylene carbonate, fluoroethylene carbonate, 4-vinyl-1,3-dioxolan-2-one, dimethyl sulfone, methyl butyrate, ethyl propionate, trimethyl phosphate, triethyl phosphate, gamma-butyrolactone, 4-methylene-1,3-dioxolan-2-one, methylene ethylene carbonate, 4,5-dimethylene-1,3-dioxolan-2-one, allyl ether, triallyl amine, triallyl cyanurate, triallyl isocyanurate, water, carbonate, fluorobutane, or tetrahydropyran. 
     
     
       29. The method of  claim 23 , further comprising:
 forming a third electrolyte solution, the third electrolyte solution including a third salt and a third electrolyte solvent; and 
 combining the third electrolyte solution with the first electrolyte solution and the second electrolyte solution to form the electrolyte mixture. 
 
     
     
       30. The method of  claim 29 , wherein the third salt includes at least one of lithium bis(fluorosulfonyl)imide (F 2 LiNO 4 S 2 ), lithium bis(trifluoromethylsulfonyl) imide (LiC 2 F 6 NO 4 S 2 ), lithium bis(oxalato)borate, lithium hexafluorophosphate (LiPF 6 ), lithium hexafluoroarsenate (LiAsF 6 ), lithium bis(trifluoromethane) sulfonimide (LiN(SO 2 CF 3 ) 2 ), lithium trifluoromethanesulfonate (LiCF 3 SO 3 ), lithium perchlorate (LiClO 4 ), lithium difluoro oxalato borate (LiBF 2 (C 2 O 4 )), lithium iodide (LiI), lithium bromide (LiBr), lithium chloride (LiCl), lithium hydroxide (LiOH), lithium nitrate (LiNO 3 ), lithium 2-trifluoromethyl-4,5-dicyanoimidazole (LiTDI), lithium sulfate (LiSO 4 ), lithium difluorophosphate (LiPO 2 F 2 ), lithium tetrafluoroborate (LiBF 4 ). 
     
     
       31. A method of forming an electrolyte, comprising:
 forming a first electrolyte solution, the first electrolyte solution including about 26 wt % to about 70 wt % of a first salt including bis(fluorosulfonyl)imide ions and about 30 wt % to about 74 wt % of a first electrolyte solvent; 
 forming a second electrolyte solution, the second electrolyte solution including about 2 wt % to about 42 wt % of a second salt and about 38 wt % to about 98 wt % of a second electrolyte solvent different from the first electrolyte solvent; and 
 combining the first electrolyte solution and the second electrolyte solution to form the electrolyte such that the electrolyte includes about 10 wt % to about 90 wt % of the first electrolyte solution and about 10 wt % to about 90 wt % of the second electrolyte solution, wherein the electrolyte comprises: 
 about 10 wt % to about 42 wt % of a product solvent, the product solvent including a mixture of the first electrolyte solvent and the second electrolyte solvent; 
 about 13 wt % to about 43 wt % of a fluoroether (FE); and 
 about 22 wt % to about 43 wt % of the first salt, wherein the FE includes a compound having the following structure: 
 
       
         
           
           
               
               
           
         
         where n1 and n2 each have values between 1 and 5, X=F, Br, Cl, or I, and n=1. 
       
     
     
       32. The method of  claim 31 , wherein the electrolyte includes about 20 wt % to about 30 wt % of the first electrolyte solution and about 70 wt % to about 80 wt % of the second electrolyte solution. 
     
     
       33. The method of  claim 31 , wherein:
 the first electrolyte solvent includes at least one of 1,2-dimethoxyethane, bis-(2-fluoro-ethyl)-ether, 1,2-diethoxyethane, bis(2-methoxyethyl) ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, diethyl ether, dipropyl ether, 1,2-dipropoxyethane, dibutoxyethane, 1,2-diethoxypropane, dimethyl carbonate, 1,3-dioxolane, 1,4-dioxolane, ethyl methyl carbonate, diethyl carbonate, dimethyl sulfoxide, ethyl vinyl sulfone, tetramethylene sulfone, ethyl methyl sulfone, ethylene carbonate, vinylene carbonate, fluoroethylene carbonate, 4-vinyl-1,3-dioxolan-2-one, dimethyl sulfone, methyl butyrate, ethyl propionate, trimethyl phosphate, triethyl phosphate, gamma-butyrolactone, 4-methylene-1,3-dioxolan-2-one, methylene ethylene carbonate, 4,5-dimethylene-1,3-dioxolan-2-one, allyl ether, triallyl amine, triallyl cyanurate, triallyl isocyanurate, water, carbonate, fluorobutane, or tetrahydropyran; and 
 the second electrolyte solvent includes a fluoroether (FE). 
 
     
     
       34. A method of forming an electrolyte, comprising:
 forming a first electrolyte solution, the first electrolyte solution including about 26 wt % to about 70 wt % of a first salt and about 30 wt % to about 74 wt % of a first electrolyte solvent; 
 forming a second electrolyte solution, the second electrolyte solution including about 2 wt % to about 42 wt % of a second salt and about 38 wt % to about 98 wt % of a second electrolyte solvent different from the first electrolyte solvent, the second electrolyte solvent including a fluoroether; and 
 combining the first electrolyte solution and the second electrolyte solution to form the electrolyte such that the electrolyte includes about 10 wt % to about 90 wt % of the first electrolyte solution and about 10 wt % to about 90 wt % of the second electrolyte solution, wherein the electrolyte comprises: 
 about 10 wt % to about 42 wt % of a product solvent, the product solvent including a mixture of the first electrolyte solvent and the second electrolyte solvent; 
 about 13 wt % to about 43 wt % of the fluoroether (FE); and 
 about 22 wt % to about 43 wt % of the first salt, 
 wherein the FE includes a compound having the following structure: 
 
       
         
           
           
               
               
           
         
         where n1 and n2 each have values between 1 and 5, X=F, Br, Cl, or I, and n=1. 
       
     
     
       35. The method of  claim 34 , wherein the fluoroether includes bis(2-fluoroethyl) ether (BFE). 
     
     
       36. The method of  claim 34 , wherein the first salt includes bis(fluorosulfonyl)imide ions.